Hyaluronate lyase, properties

Effect of Streptomyces hyaluronidase. The effects of some depolymerizing enzymes on the viscoelastic properties of proteoglycan were examined. The first example was that of Streptomyces hyaluronidase (hyaluronate lyase, EC 4.2.2.1.), which is shown as strictly specific to hyaluronic acid (j6). Thus this enzyme can degrade only the hyaluronic acid backbone of aggregate and should not attack the proteoglycan monomer. To 0.1% solution of aggregate 0.05TRU of Streptomyces hyaluronidase was added. As... 

Hyaluronan is widely used in applied biochemistry and enzymology as a substrate for the quantitative determination of the enzyme hyaluronidase. Scientific disputes about the possible relationship between HA and hyaluronate lyase and the pathogenicity of some streptococci are to be, as it seems, permanently carried out. Currently, much attention is paid to the study of the secondary and tertiary structures and dynamic conformation of HA in aqueous solutions and biological fluids the HA interaction with proteins, particularly receptor CD44 and other hyaladherins and the HA biocatalytic cleavage with different hyaluronidase the progression toward creating of recombinant strains and chimera products with the desired properties. 

Bacterial hyaluronate lyases have a narrow substrate specificity. They split HA that has a higher rate in order to lower the molecular weight of the final products. At the same time, they create unsaturated oligosaccharides that are likely to have different therapeutic properties to saturated oligosaccharides. Several unsaturated oligosaccharides were isolated after a treatment with hyaluronate lyases in order to study their properties [46]. The bacterial hyaluronate lyases could help to study kinetics of HA depolymerization using spectropho-tometric methods that allow for the reaction products level of unsaturation to be identified. 

Arthrobacter aurescens secretes an enzyme that hydrolyses chondroitin sulphate. The enzyme crystallized after purification and exhibited the following properties pH optimum 6.0, temperature optimum 50 C, and pH stability 4.9—7.4 it was stable below 45 °C and hydrolysed chondroitin 4- and 6-sulphates, chondroitin, and hyaluronic acid (ratio of initial rates 1.0 1.1 1.95 3.2). The hydrolyses of chondroitin 4- and 6-sulphates furnished 2-acetamido-2-deoxy-3-0-(4-deoxy-a-L-t/irco-hex-4-enopyranosyluronic acid)-D-galactose 4- and 6-sulphates, respectively. Since the enzyme is inactive against dermatan sulphate, it is a chondroitin sulphate lyase AC. 

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